Tap block injection device

The present patent application claims priority to U.S. Provisional Patent Application Ser. No. 63/208,293, filed on Jun. 8, 2021, the entire disclosure of which is hereby incorporated herein by reference.

The present disclosure relates generally to the field of medical injection devices and, more particularly, to a device for injecting anesthetic into a patient during a laparoscopic surgical procedure, where the device includes a sheath which covers a needle while the device is maneuvered, and the sheath is retractable to expose the needle for the injection.

A transversus abdominis plane (TAP) block is a procedure to anesthetize the nerves that provide sensation and muscle function to the abdominal wall and skin of a surgical patient. For a TAP block, an anesthetic injection is administered in the area between the internal oblique and transversus abdominis muscles in the stomach wall. A TAP block reduces the use of post-surgical opioids and their related side effects. A TAP block provides more effective post-surgical pain relief (analgesia) for a longer time period than general anesthesia alone.

A TAP block may be used in open surgical procedures or in laparoscopic procedures. In open surgical procedures, the anesthetic can be administered directly by the surgeon (or other qualified personnel in the operating room) with a syringe/needle in the open body cavity where both access and visibility are good. In laparoscopic procedures, however, access is limited to the small laparoscopic incision(s) or ports, and there is no direct visibility of the surgical field or the needle used for anesthetic injection. With existing injection needles, the limited visibility and maneuverability inherent in laparoscopic procedures increases the risk that the needle will inadvertently puncture an organ or tissue other than the intended transversus abdominis muscle.

In light of the circumstances described above, there is a need for an improved TAP block injection device for use in laparoscopic procedures.

The present disclosure describes an injection device for performing a transversus abdominis plane (TAP) block anesthetic administration during a laparoscopic surgical procedure. The device includes a handle, a needle fixed to the handle, and a sheath covering the needle. The sheath is slidably retractable via a thumb-operated slider on the handle. In a first position for device insertion and maneuvering, the sheath fully covers the tip of the needle, preventing the needle from puncturing or lacerating any organ or tissue in the patient. In a second position for injection, the sheath is retracted using the slider to expose the tip of the needle, enabling insertion of the needle tip into the appropriate tissue and injection of the anesthetic. The needle and sheath have a length suitable for reaching the desired location internal to the body cavity from outside the patient's body through the laparoscopic incision. A standard threaded luer and tube are fluidly coupled to the needle, where a syringe is attachable to the luer and used to push the anesthetic through the needle and into the tissue.

Additional features of the presently disclosed devices will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.

The following discussion of the embodiments of a TAP block injection device is merely exemplary in nature, and is in no way intended to limit the disclosed devices and techniques or their applications or uses.

A transversus abdominis plane (TAP) block is an anesthetic injection administered to the transversus abdominis muscles in the stomach wall of a patient in order to block pain from surgical incisions. TAP block techniques during abdominal surgeries have expanded in use because the patient recovers more quickly after surgery and associated complications are reduced when a TAP block is used. Furthermore, TAP block techniques decrease reliance on the use of opioids, which can be highly addictive and have been linked to premature deaths. Opioid addiction is a major societal problem and, consequently, wide scale efforts are targeted to reduce reliance on these drugs. Despite the increased use and benefits of TAP block techniques, tools used to perform them need improvement. In addition, there is a dearth of TAP block tools that can be used in conjunction with minimally invasive laparoscopic procedures, whereby the same ports can advantageously be used for both laparoscopic surgery and TAP block techniques to decrease the number of total incisions needed.

The present disclosure describes a device used to perform TAP block injections during laparoscopic procedures. The disclosed device is designed to overcome the limitations of existing tools. The disclosed device offers a dramatic improvement over existing bare injection needles which, whether creating their own puncture hole as advanced into the abdomen or passed through a laparoscopic incision, can inadvertently puncture organs or tissue other than the desired injection target muscle.

The presently disclosed device is designed to be inserted through the laparoscopic incision/port with the needle safely covered by a sheath to prevent puncture of any organ or tissue. The device is advanced into the body cavity and maneuvered into a position where the needle tip, still covered by the sheath, is in the body cavity and pointed outward toward the exterior of the body. When the device is properly positioned in the abdominal cavity, the sheath is retracted and the needle tip is exposed for muscular injection. This design enables the operator, when piercing tissue with the needle, to advance the needle tip from within the body outwardly through tissue, towards the exterior of the body, in a controlled and precise manner to position the needle tip accurately to administer a medicinal substance. The device is designed to puncture through tissue, such as a muscle layer, while providing tactile feedback to the operator during needle insertion.

Throughout the present disclosure, the term “operator” will be used to describe the person who is operating the disclosed TAP block injection device. It is to be understood that the operator may be a surgeon, an anesthesiologist, or any other qualified person who is in the operating room.

The device can be inserted through the same laparoscopic port created in a body to pass devices into and out of that body to access surgical sites, such as a diseased organ, without having to make large abdominal incisions. Used in this manner, the device of the present disclosure enables advancement of the needle through tissue layers, such as muscle, to administer anesthetic agents between muscle layers or to other targeted areas within the body. Importantly, features of this device enable tactile feedback to the operator that signals when the needle tip “pops” through tissue, thus helping to enable an operator to position the needle tip in the fascial layers between muscle tissue, for example. In addition, the direction of insertion of the needle is from within a body towards the outside of that body, which offers a safety advantage over current TAP block techniques that insert the needle from outside the body to within a body, which can lead to unwanted organ perforation or damage by the needle.

The device of the present disclosure includes a slider-type control mechanism on the handle to control and lock the position of the sheath relative to the needle tip. The device also includes a magnetic positioning feature which provides a detent-type tactile feel indicating the position of the slider and thus the position of the sheath relative to the needle tip. The device of the present disclosure can be used in conjunction with imaging equipment that can include ultrasound or fluoroscopic systems to provide visualization within a body to further guide precise needle tip placement.

1 FIG. 2 FIG. 1 2 FIGS.and 100 100 100 110 130 110 140 150 140 150 110 160 150 164 160 150 is a first isometric view illustration of a TAP block injection device, according to an embodiment of the present disclosure.is a second isometric view illustration of the TAP block injection device, according to an embodiment of the present disclosure. The deviceis comprised of a handle, a sliderslidably disposed on the handle, a sheathand a hypodermic needle(inside the sheathand not visible in). The needleis fixedly attached to the handle, and an injection port tubeis in fluid communication with the needle, such that a reservoir such as a syringe (not shown) can be attached to a luerand used to push a liquid such as anesthetic through the tubeand the needle.

140 130 130 110 130 130 140 150 150 100 130 110 140 150 1 2 FIGS.and 2 FIG. The sheathis coupled to the slider. The slidercan slide along the top of the handlefor a limited travel distance, and has features for locking into different positions. In a preferred embodiment shown in the figures, the slideris lockable in three different positions. When the slideris advanced to the fully-forward position as in(indicated at {circle around (1)} in), the sheathfully covers the tip of the needle. In this “safe” position, there is no risk of the needleinadvertently puncturing or perforating any body tissue while the deviceis being maneuvered into position in the body, because the needle tip is not exposed. When the slideris moved back on the handleto a second position ({circle around (2)}) or a third position ({circle around (3)}), the sheathis retracted to expose the tip of the needleby a corresponding amount. By way of non-limiting example, at the slider's second position ({circle around (2)}) the exposed portion of the needle tip may be 0.75 cm, and at the slider's third position ({circle around (3)}) the exposed portion of the needle tip may be 1.5 cm. The different lengths of exposed needle tip allow the operator control over the amount of needle penetration into the target muscle.

130 140 150 130 110 130 110 140 150 The locking feature of the slider(discussed later) ensures that the sheathstays in the operator's desired position relative to the needle. In addition, a magnetic positioning feature is included in the sliderand the handle. The magnetic positioning feature (also discussed later) provides tactile feedback to the operator as to the position of the sliderrelative to the handle, and thus the position of the sheathrelative to the tip of the needle, so that the operator can concentrate on the position of the needle tip and does not have to look at the slider/handle position.

100 142 140 150 140 130 150 110 100 160 140 150 110 The deviceis designed and sized to allow a distal endof the sheathto be advanced into the body cavity through a laparoscopic port, and positioned on an inside fascia of a target muscle pointing in an outwardly direction relative to the patient's body, with the needlefully covered during this insertion and maneuvering. The sheathis then retracted by sliding the sliderto the second or third position, the needleis advanced into the muscle by pushing the handlein that direction, and the injection is then administered. In one non-limiting example, the device(excluding the tube) has an overall length of about 16 inches, of which 12 inches is the length of the sheathand the needle, and 4 inches is the length of the handle. Larger or smaller dimensions may be used as suitable for particular TAP block injections.

3 FIGS.A 3 FIG.A 1 2 FIGS.and 3 3 100 150 140 100 130 142 140 150 100 100 /B/C are side view illustrations of the TAP block injection devicein three different positional configurations, where the needleis fully covered by the sheathor the needle tip is exposed, according to an embodiment of the present disclosure. In, the deviceis in the same configuration as shown in—that is, with the slideradvanced to the fully-forward position ({circle around (1)}), and the distal endof the sheathfully covering the tip of the needle. This is the configuration that is used for insertion of the deviceinto the patient's body through the laparoscopic port and positioning of the devicebefore the injection.

3 FIG.B 3 FIG.C 100 130 140 150 150 150 100 130 140 150 150 150 In, the deviceis in a configuration with the sliderin the middle position ({circle around (2)}), and the sheathpartially retracted to expose the tip of the needle(by 0.75 cm in one embodiment). This is a configuration that can be used for advancing/penetrating the tip of the needleinto the target muscle tissue and injecting the anesthetic. In particular, this configuration would be used when only a limited penetration (0.75 cm) of the needleinto the target muscle tissue is desired. In, the deviceis in a configuration with the sliderin the fully-aft position ({circle around (3)}), and the sheathretracted to expose more of the tip of the needle(1.5 cm in one embodiment). This is also a configuration that can be used for advancing/penetrating the tip of the needleinto the target muscle tissue and injecting the anesthetic. In particular, this configuration would be used when a greater penetration (1.5 cm) of the needleinto the target muscle tissue is desired.

4 FIG. 3 FIG.C 4 FIG. 4 FIG. 100 142 140 140 130 140 130 152 150 150 110 is a close-up illustration of the TAP block injection devicein the configuration of, where the needle tip is exposed, according to an embodiment of the present disclosure. The distal endof the sheathis visible in. The opposite end of the sheath, the proximal end, is attached to the slideras discussed above and shown in later figures. The sheathhas been retracted from the needle tip by moving the sliderto the third (fully-aft) position. A distal endof the needle, also referred to as the needle tip, is also visible in. The opposite end of the needle, the proximal end, is fixedly mounted inside the handle, as mentioned earlier and shown in later figures.

150 The needle tip is sharpened to an angle that preserves tactile feedback to the operator as it penetrates tissue. The preferred angle of the sharpened needle tip is 45 degrees. A 45-degree angle of the needle tip provides an optimal balance of force required to penetrate tissue while preserving tactile feedback of the needle tip during use. When penetrating a fascial layer of muscle tissue, the optimized needle angle exhibits a “pop” sensation to the operator as he or she advances the needlethrough the tissue layer. The “pop” sensation is an indicator that the needle tip has exited one layer of tissue and that the needle tip may be in the interstitial space between layers of tissue, such as muscle.

150 150 150 Other tip angles also provide acceptable performance. The needle tip angle can range from around 30 degrees to around 60 degrees, with 45 degrees being the preferred sharpened tip angle. The needlecan be made from any material commonly used for hypodermic needles, such as medical grade 304 or 316 stainless steel. Other grades of stainless steel used in the medical device industry for hypodermic needles can also be used. It is also contemplated that other materials like a shape memory alloy, such as nitinol may also be used for the needle. The inner and outer diameter, ID and OD respectively, of the hypotube used to make the needlecan be of any size commonly utilized to administer anesthetic agents. For example, a 27-gauge needle tube with an ID of 0.21 mm and OD of 0.413 mm with a nominal needle wall thickness of 0.102 mm is suitable in this application. Alternatively, other hypotube sizes, such as a 25 or 30 gauge can be used. Still other hypotube sizes can also be used.

150 150 150 In a preferred embodiment, the needleis straight as shown in the figures. In other embodiments, the needlemay be curved in any amount and any direction to suit a particular application. The shape memory alloy mentioned above may be used to increase or decrease needle curvature or change the shape of curvature (by heating the needle) during the TAP block procedure. For example, a needle shape with little or no curvature may be best suited for accessing a first TAP block injection site, and a needle shape with significant curvature may be best suited for assessing a second TAP block injection site during the same laparoscopic surgical procedure.

100 150 The deviceof the present disclosure can be used in conjunction with imaging equipment that can include ultrasound or fluoroscopic systems to provide visualization of the needlewithin a patient's body to further guide precise needle tip placement.

140 140 140 130 130 140 140 140 110 140 130 142 140 140 140 150 140 150 150 140 The operation of the sheathhas been discussed above—where the sheathfully covers the needle tip on one configuration, the sheathis connected to the slider, and movement of the sliderallows the sheathto be retracted from the needle tip. In one embodiment, the working length of the sheathcan be 12 inches (30 cm) and its diameter can be 0.125 inches (3.2 cm). Other sheath working lengths and diameters can be used. The sheath working length is the length of the sheathfrom the distal end of the handle(where the sheathconnects to the slider) to the distal endof the sheath. This sheath working length is available to insert into a patient's body. The sheathcan be made from a variety of materials that include flexible polymers to inflexible metallic tubing. Examples of suitable polymers include biocompatible polyurethane, nylon, polycarbonate, polyether block amide (PEBA), polyethylene, and other polymer materials commonly used in medical devices used within the body. The sheathcan also be made of a variety of medical grade stainless steel or a shape memory alloy such as nitinol, in designs compatible with the shape and material of the needle. The inner diameter of the sheathis larger than the outer diameter of the needle, thus enabling free movement of the needlewithin the sheath.

5 FIG. 1 2 3 5 FIGS.,,A and 3 FIG.B 3 FIG.C 110 100 130 140 130 130 150 130 110 140 130 110 130 130 110 130 130 150 130 140 is a partially cut-away illustration of the handleof the TAP block injection device, showing operational details of the sliderfor positioning the sheath, according to an embodiment of the present disclosure. The slideris designed to be thumb-operated by the operator. As discussed previously, the operator manually advances or retracts the position of the sliderto vary the exposed length of the needle. Throughout the present disclosure, slider positions described as “advance(d)” and “fully-forward” correspond to the first position ({circle around (1)}) of the sliderrelative to the handle, as illustrated in, where the needle tip is fully covered by the sheath. Slider positions described as “partially retracted” correspond to the second position ({circle around (2)}) of the sliderrelative to the handle, where the slideris in this position in. Similarly, slider positions described as “fully retracted” and “fully-aft” correspond to the third position ({circle around (3)}) of the sliderrelative to the handle, where the slideris in this position in, and the position is designated by the {circle around (3)} in other figures. The slidercan be retracted from the fully-forward position (where no portion of the needleis exposed) to a partially-retracted or fully-retracted position where the needle tip is exposed. The slidercan be advanced from a partially-retracted or fully-retracted position to the fully-forward position to completely cover the needle tip with the sheath.

130 140 132 130 140 132 130 140 132 140 132 130 130 110 140 150 150 110 150 160 164 150 5 FIG. The slideris attached to the sheathat a coupler, so the sliderand the sheathmove together. The couplerand the slideroperate as a single part, and can be molded as a single-piece unit, or molded separately and joined together. The sheathis pressed and/or bonded into an aperture in the coupler, so that the sheathis permanently fixed to the couplerand thus the slider. The sliderslides along the handle, thus controlling the position of the sheathwith respect to the needle, where the needleis immovably affixed within the housing of the handleas shown in. The proximal end of the needleis in fluid communication with the interior of the injection port tube, so that anesthetic from a reservoir (e.g., syringe) coupled to the luercan be pushed through the needle.

130 134 130 110 140 150 134 112 110 134 130 130 110 134 134 112 130 110 112 112 130 112 134 112 130 110 140 150 5 FIG. 6 FIG. 5 FIG. The sliderhas a slider lock buttonto immobilize the position of the sliderrelative to the handle, and thus lock the position of the sheathrelative to the needle. The slider lock buttonis spring-loaded (“upward” in) and has a shape feature designed to lock into notcheson an upper interior surface of the handle. These features are shown inand discussed further below. Depressing the slider lock button(by the thumb of the operator) releases the sliderto enable the sliderto move back and forth along a track of the handle. When the slider lock buttonis released, the spring-loading pushes the buttonupward to engage one of the notchesand lock the sliderin position with respect to the handle. In the preferred embodiment, there are three of the notches. The locations of the notchescorrespond to the positions ({circle around (1)}, {circle around (2)} and {circle around (3)}) of the slider, where the aft-most two of the notchesare visible in. When the slider lock buttonis locked into position in one of the notches, the slideris immobilized relative to the handle, and the sheathis thus fixed in position relative to the needle.

100 130 110 130 110 134 110 130 138 130 118 110 118 130 118 118 5 FIG. 6 FIG. In addition to the slider position locking feature discussed above, the deviceincludes a magnetic positioning feature in the sliderand the handle. The magnetic positioning feature provides tactile feedback to the operator as to the position of the sliderrelative to the handle, while the slider lock buttonis depressed, so that the operator can concentrate on the position of the needle tip and does not have to look at the handlein order to determine the position of the slider. In a preferred embodiment, the magnetic positioning feature includes a magnet rodfitted transversely into the slider, and pairs of steel pinsfitted into the left and right sides of the handle. A left/right pair of the steel pinsis provided for each of the lock positions ({circle around (1)}, {circle around (2)} and {circle around (3)}) of the slider; thus, there are three pairs of the pinsin the preferred embodiment. One of the steel pinsis visible in. Further details are shown in.

138 118 134 112 130 134 130 134 112 130 The magnet rodaligns with one of the pairs of steel pinswhen the slider lock buttonis aligned with one of the notches, thus providing a detent-type feel to the operator indicating that the slideris in one of the three positions. In this way, when the slider lock buttonis released with the sliderat one of the three notch positions, the slider lock buttonsnaps up into one of the notchesand the slideris locked in position.

150 140 132 130 5 130 140 130 140 100 140 150 140 130 The needleinside the sheathserves to guide the couplerand the sliderin controlled linear fore/aft motion, as seen in FIG.. The travel distance of the sliderdictates the length of travel of the sheath. There is a 1:1 correlation between the length of the movement of the sliderand the sheath. The total travel distance is designed to be 1.5 cm in the preferred embodiment. However, other total travel distances are contemplated. Similarly, the deviceof the present disclosure can be designed to offer a variety of amounts of exposed needle tip. In the embodiment shown in the figures of the present disclosure, the operator can advance the sheathto cover the needlecompletely, or retract the sheathto expose 0.75 cm of the needle tip, or expose 1.5 cm of the needle tip, depending on the position of the slider. Other slider/sheath position combinations are readily envisioned and possible—such as a two-position design (needle covered vs. exposed), a four-position design, etc. In other embodiments, the distances between the slider lock positions need not all be the same, and the maximum possible amount of exposed needle tip may be more or less than the 1.5 cm of the embodiment discussed above.

110 110 114 110 110 110 116 110 116 110 130 The handlehas a shape designed to fit the operator's hand (either hand), where the index finger is wrapped around the handleand positioned in a recesson the bottom of the handlenear the front, and the three other fingers are wrapped around the handleand positioned on the bottom of the handleat the middle and rear as indicated at. Features are provided to ensure a positive grip on the handle, such as grooves or a knurled surface, particularly in the middle and rear as indicated at. The operator's thumb is positioned on the top front of the handleto operate the slider.

6 FIG. 100 110 120 110 122 124 110 140 150 150 140 154 150 160 150 160 110 122 124 122 124 is an exploded-view illustration of the TAP block injection device, according to embodiments of the present disclosure. In one design embodiment, the handleis constructed of three pieces—including a handle gripwhich makes up the lower portion of the handle, and a handle left halfand a handle right halfwhich make up the left and right sides and upper portion of the handle, respectively. Other handle construction embodiments are also possible. The sheathand the needleare shown as described previously—where the needleis positioned inside the sheath. A proximal endof the needleis fitted into the injection port tubeand the needleand the tubeare fixed to the handle, such as by snapping into clips molded into one or both of the handle half parts/and being held in place between the handle left halfand the handle right half.

140 130 132 130 110 140 150 5 FIG. The sheathis fixed to the sliderat the coupler(labelled on). Thus, fore/aft movement of the sliderrelative to the handlecauses the sheathto extend or retract relative to the needle, as described in detail above.

134 130 128 134 128 134 136 134 136 112 110 112 124 134 128 136 112 130 134 136 134 112 130 6 FIG. The slider lock buttonfits into a hole in the top of the slider. A compression springis installed in the hole before the slider lock button, where the springprovides an upward bias force on the bottom of the slider lock button. A shoulderis a shape feature located on each side of the slider lock button. The shoulderfits into the notchesin the handle. The three notchesare visible in the handle right halfin. When the slider lock buttonis depressed, compressing the spring, the shoulderis displaced downward out of whichever of the notchesit was in, and the slideris free to move fore and aft. When the slider lock buttonis released with the shoulderaligned with one of the three notch positions, the slider lock buttonsnaps up into one of the notchesand the slideris locked in position.

6 FIG. 118 126 122 124 118 130 110 126 124 126 122 138 130 130 138 118 130 110 138 136 130 126 112 122 124 138 118 136 112 130 130 134 110 Details of the components of the magnetic positioning feature are also clearly visible in. A plurality of the steel pinsare fitted into holesin the handle left halfand the handle right half. Specifically, a pair of the steel pins(one each on left and right sides) is provided for each locking position of the sliderrelative to the handle. Three of the holesare visible in the handle right half; three of the holesare provided at corresponding (directly opposite) locations in the handle left half. The magnet rodis fitted transversely into the slider. When the slideris moved fore/aft, the magnet rodis attracted to align with one of the pairs of the steel pins, thus providing a strong tactile feel to the operator as to the position of the sliderrelative to the handle. The fore/aft positions of the magnet rodrelative to the shoulderin the slider, and the holesrelative to the notchesin the left and right handle halves/, are designed such that when the magnet rodis aligned with one of the pairs of pins, the shoulderis aligned with a corresponding notch. In this way, when the operator feels the detent-type click of magnetic alignment, he/she knows which position ({circle around (1)}, {circle around (2)} or {circle around (3)}) the slideris in, and knows that the sliderwill lock into that position when the slider lock buttonis released. This tactile slider position feedback is important in that it allows the operator to concentrate on the needle tip placement displayed on an imaging system during the surgical procedure, and not have to look at the handlein order to determine slider position.

162 160 164 162 150 150 160 150 160 164 150 160 160 150 160 164 162 164 An injection port assemblyis comprised of the tubewhich is a flexible polymer tube, and the luerwhich is a standard threaded luer. This assembly, in turn, is attached to the needle, with the needlepressed into the tube. The needle, the tubeand luerare fused together to ensure that there are no leaks at each of the joints between the different components. The method of fusing or bonding the needleto the tubecan include a self-bonding friction fit, adhesive bonding or heat boding to attach the tubedirectly onto the needle. Similarly, the tubeis bonded to the luerusing either adhesive or heat bonding so that no leaks occur between the components. Examples of suitable polymers for the flexible polymer tubing in the injection port assemblyinclude biocompatible polyurethane, nylon, polycarbonate, PEBA, polyethylene and other polymer materials commonly used in medical devices. The standard threaded lueris an off the shelf component made from polycarbonate, or other similar materials, and is widely available to medical device manufacturers from component suppliers.

140 100 100 100 100 The sheathof the deviceis designed to fit through a 5 mm laparoscopic port. An adaptor could be fit to allow the deviceto be used with any size port. The devicecan also be used with a da Vinci surgical robot through a port adapter. Additionally, the deviceof the present disclosure could be adapted to fit into a da Vinci arm and, therefore, be manipulated and positioned by the da Vinci surgical robot.

7 FIG. 700 702 100 140 150 704 142 140 706 142 140 is a flowchart diagramof a method for performing a TAP block anesthetic injection during a laparoscopic surgical procedure, according to an embodiment of the present disclosure. At box, the deviceis provided in a first configuration where the sheathis extended and locked to fully cover a needle tip of a hypodermic needle. At box, the distal endof the sheathis inserted into a laparoscopic port of a patient. At box, the distal endof the sheathis directed towards the abdominal wall and positioned at a target injection site inside the patient.

708 140 130 110 100 134 130 150 140 150 150 710 At box, the sheathis retracted to expose a desired amount of the needle tip, using the slideron a handleof the injection device. The operator depresses the slider lock buttonwhile simultaneously pulling back on the sliderto expose the tip of the needle. The sheathis locked in a position which exposes the desired amount of the tip of the needle. Once the tip of the needleis exposed, at box, the needle tip is advanced into the desired plane of the transverse abdominal muscle tissue at the target injection site, where the operator feels the distinctive “pop” when entering fascial tissue.

712 164 100 164 At box, the anesthetic injection is performed by expelling anesthetic from a syringe connected to the luer. The surgeon can either perform the injection of local anesthetic himself/herself, or can have an assistant (other operator) perform the injection as the deviceof the present disclosure design allows for either method, depending on surgeon preference. The injection is performed by pressing a plunger on a syringe attached to the luer, in a known manner. During the injection, the operator will notice a bulge of the transverse abdominal muscle as the pressure from the local anesthetic in the fascial plane pushes the thin muscle into the abdominal cavity, resulting in the appearance of said bulge, which is a sign of proper needle positioning and infusion of the anesthetic agent.

140 150 150 714 134 130 150 140 150 At this point, if additional anesthetic needs to be injected at a greater depth in the muscle, the operator can retract the sheathto expose a greater amount of the tip of the needle, then insert the needlethe additional distance into the muscle, and again perform an injection. After the desired amount of local anesthetic has been administered, at boxthe operator presses the slider lock buttonand moves the sliderforward to fully cover the needlewith the sheath, while withdrawing the tip of the needlefrom the muscle.

716 140 100 140 150 At box, the sheathis withdrawn from the laparoscopic port of the patient. The operator then performs the same technique on the contralateral side. All insertion, maneuvering and withdrawal of the devicein and from the patient occurs with the sheathlocked in the fully-forward position and fully covering the needle, thus ensuring that no inadvertent puncture, perforation or laceration of tissue or organs occur.

100 700 The deviceand the method of the flowchartcould also be used to perform injections at other sites besides the transversus abdominis muscles, in any application which benefits from a device which can be inserted into a laparoscopic port, safely maneuvered inside the body with the needle tip covered, then re-configured to expose the needle tip and perform the injection.

100 100 The presently disclosed TAP block injection deviceoffers many advantages over existing tools. The devicecan be advanced through the same laparoscopic port created in a body to pass devices into and out of that body to access surgical sites, such as a diseased organ, without having to make large abdominal incisions. Used in this manner, the device of the present disclosure enables advancement of the needle through tissue layers, such as muscle, to administer anesthetic agents between muscle layers or to other targeted areas within the body. Importantly, features of this device enable tactile feedback to the operator that signals when the needle tip “pops” through tissue, thus helping to enable an operator to position the needle tip in the fascial layers between muscle tissue, for example. In addition, the direction of insertion of the needle is from within the body towards the outside of that body, which offers a safety advantage over current TAP block techniques that insert the needle from outside the body to within the body, which can lead to unwanted organ perforation or damage by the needle. The sheath-covered needle provides a tremendous safety advantage over existing tools, and the convenient means of retracting the sheath for injection provides the necessary device control, including tactile feedback of configuration, while allowing the operator to concentrate on device positioning rather than operation.

While a number of exemplary aspects and embodiments for a TAP block injection device have been discussed above, those of skill in the art will recognize modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope.